These activities work for either a hedgehog or a porcupine theme although I was usually thinking "hedgehog" when I came up with them.

Hedgehogs and porcupines are both small mammals with spiny/spiky hair -- the big difference is that a hedgehog's spines don't come out whereas a porcupine's quills are released to jab into potential predators when the porcupine feels threatened. Youch!